VO 2 films were prepared on glass and KBr substrates by DC reactive magnetron sputtering.The morphology,crystallization and molecular structure of the films were studied by scanning electron microscope(SEM),X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FT-IR),respectively.Results reveal that the particles of films prepared by annealing in oxygen become clearly visible,and the average particle size is about 25 nm.After annealing,the structure of films is changed from amorphou...